The present invention in general encompasses the field of analog integrated circuit design, and in particular embodiments, analog circuit design of programmable gain amplifiers in low power supply environments.
As integrated circuit voltages continue to decrease, relatively high input signals can turn on devices within circuits at times when they should not be turned on. There is therefore a need in the art for circuitry which is less sensitive to accidental turn on of components.
The invention discloses embodiments of programmable gain attenuators (PGAs). In an example PGA an input receives an input signal to be amplified. A plurality of impedances divide the signal into a plurality of voltage levels. A plurality of amplifiers receive the voltage levels. Only the selected amplifier is provided with power and the others are disconnected from power.